Being physically attractive can also literally pay off, as many people believe it can mean you make more money. In short, beautiful people are more confident, have more social skills, and are seen as more able by employers, which translates to higher wages.

Satoshi Kanazawa from the London School of Economics and Political Science and Mary Still from the University of Massachusetts in Boston analysed data from a study of 20,000 young Americans. They were interviewed and measured on physical attractiveness at age 16 then three more times until they were 29.

The findings showed that the theory there is a "ugliness penalty" on wages isn't that simple. When other traits were taken into account, such as health and intelligence, results showed people who were more conscientious, extroverted, and less neurotic earned significantly more than others.

Also, participants who were labeled as "very unattractive" always earned more than those who were just "unattractive." This was also sometimes the case when very unattractive people were compared to those who were average-looking and attractive.

Alex Fradera offers an explanation for this in BPS Digest. He said the personality trait "Openness to Experience" may have been surprisingly correlated with lower earnings and higher attractiveness in this particular data set, when it is usually associated with higher pay.

"Could this Openness-attractiveness association be an indicator that some of the very unattractive scored especially low on Openness, and were perhaps highly devoted to a specific topic area, pursuing it obsessively to the exclusion of all distractions and eventually entering the forefront of their field?" he wrote. "We know that Openness correlates negatively with the passion component of 'Grit,' so such effects are conceivable."

Still said the methods of previous studies may not have accounted for the really ugly people because the "very unattractive" and "unattractive" are often lumped in together in one group.

"Thereby they fail to document the ugliness premium enjoyed by the very unattractive workers," she said.